Electrical power cables are ubiquitous and used for distributing power across vast power grids or networks, moving electricity from power generation plants to the consumers of electric power. Power cables characteristically consist of a conductive core (typically copper or aluminum) and may be surrounded by one or more layers of insulating material. Some power cables include a plurality of conductive cores. Power cables may be constructed to carry high voltages (greater than about 50,000 Volts), medium voltages (between about 1,000 Volts and about 50,000 Volts), or low voltages (less than about 1,000 Volts).
As power cables are routed across the power grids to the consumers of electric power, it is often necessary or desirable to periodically form a splice or junction in the cable so that electricity may be distributed to additional branches of the grid. The branches may be further distributed until the grid reaches individual homes, businesses, offices, and so on. For example, a single power cable supplying electrical power to a group of several buildings must be branched to each of the buildings. As used herein, the terms “splice” and “junction” are used interchangeably, and in each case refer to the portion of a power distribution system where an incoming cable is connected to at least one outgoing cable.
At each point where the cable is connected, it is necessary to provide some type of branch connector or splice or termination on the cable. Up to the present time, branches in cables have commonly been made using pre-formed branch connectors having a predetermined type and fixed number of branches.
The current products for splicing power cables to form branches have disadvantages. For example, the splice products (sometimes referred to herein as “branch connectors”) must be purchased having a predetermined and fixed number of connection ports. This requires the end user to accurately anticipate the future connection requirements at each splice location, and then purchase a branch connector to meet the anticipated future needs. In other words, if the anticipated future need is to have four electricity services, a five-port splice must be initially installed to allow for the incoming supply cable and the four outgoing service cables. In addition, to provide a “safety margin” to accommodate possible future expansion, the end user will generally install a splice having an additional connection port beyond the current anticipated needs. Therefore, a six-port splice is installed on the incoming supply cable, when the anticipated need is for only four outgoing service cables to be installed in the future. This over-building leads to wasted capital expenditures, in the form of unused ports installed in the power distribution system. Further, if future expansion of the power distribution system eventually exceeds the original anticipated needs and any extra ports that may have been originally installed, then an entirely new splice with additional connection ports must be installed. The installation of a new splice requires the disconnection and disruption of service of all existing service cables extending from the original splice, and then reconnection to a new larger splice product. Of course, the new splice product will typically have unused ports and the associated wasted capital, just like the original splice product.
An additional problem with the current splice product configurations is the large number of products that must be manufactured and inventoried to provide for all of the possible splice requirements in terms of the number of connections required. For example, a typical splice product family might contain five different configurations, with each configuration having a different number of connection ports (i.e., two ports, three ports, four ports, five ports, six ports). Some product families need as many as ten different number of port configurations. The large number of product variations, just in terms of the number of connection ports, leads to significantly higher manufacturing costs for the supplier and higher inventory costs for the end user.
Additionally, there is an increased number of splice product configurations due to the many different types of cable constructions, configuration, and sizes required for different power distribution applications. For example, a business may require a power service with a 1,000 MCM power cable, a house may require service with a 4/0 AWG power cable, and a streetlight may require service with a #12 AWG cable. These cables could be stranded or solid, aluminum or copper, with different insulation composition types and thickness.
The complexity of the splice product families, due to the number and type of port configurations, can also lead to reduced productivity for the end user. Specifically, the complexity of the splice product families leads to additional time spent by the installers determining the correct splice product configuration for the current installation (i.e., examining the installation site requirements and reviewing product offerings to find the product that best meets the requirements), and actually obtaining the correct product (i.e., trips to the truck and back, or trips to the warehouse and back if the correct product is not in stock on the truck, etc.).
New neighborhoods and buildings (and thus new cable branches) are constantly being added to the power grid, and existing networks are constantly being modified. Therefore, a need exists for a branching connector that allows for easy expansion of the power distribution system, and that is readily adaptable for different numbers of outgoing service cable branches from an incoming supply cable. Further, because many different types and sizes of cables are used in the power transmission industry, it is desirable to have a branching connector that is easily adaptable for connection to a large variety of cable types in order to reduce manufacturing, handling and inventory costs associated with building and maintaining a large inventory of diverse connectors. Further, it is desirable to have an expansion connection capability to improve installer productivity by simplifying the planning process and eliminating undesirable trips from the field to the warehouse. It is further desirable for the ability to add expansion ports without disrupting existing service connections. It is further desirable for such connectors to be able to interconnect cables in as cost-effective manner as possible.